Sheet pull-back mechanism



Jan. 15, 1963 w. H BAUER SHEET PULL-BACK MECHANISM 6 Sheets-Sheet 1 Filed March 31, 1958 NW 1] M N% bu 1a NQQ o INVENTOR WZzZHzerfi. Jaiier M 0425 ATf RNEYS Jan. 15, w H BAUER SHEET PULL-BACK MECHANISM INVENTOR 6 Sheets-Sheet 2 m ATTORNEYS Filed March 51, 1958 Jan. 15, 1963 BAUER 3,073,593

SHEET PULL-BACK MECHANISM Filed March 51, 1958 6 Sheets-Sheet 3 7 III! Q 41 l a; INVENTOR 1 A I M Z) Z WQZZZzeI'HJ ATTORNEYS Jan. 15, 1963 w. H. BAUER SHEET PULL-BACK MECHANISM 6 Sheets-Sheet 5 Filed March 51, 1958 INV ENT OR ATTORNEY5 JW F g WaZZkerMZaizkn w m m W. H. BAUER Jan. 15, 1963 SHEET PULL-BACK MECHANISM 6 Sheets-Sheet 6 Filed March 51, 1958 bw MF VH F INVENTOR mfi HE i United States Patent 3,073,593 SHEET PULL-BACK IVHECHANISM Walther H. Bauer, Hinsdale, lll., assignor to Continental Can Company, Inc., New York, N .Y., a corporation of New York Filed Mar. 31, 1958, Ser. No. 725,056 20 Claims. (Cl. 271-60) This invention relates primarily to a machine in which a metal sheet is slightly over-fed, step-by-step, along a support extending to a mechanism for operating upon said sheet, and in which the sheet is back-fed to an accurate position against a back-gage after each advancing step, to effect precision positioning of the sheet before the aforesaid mechanism operates. An example of such a machine is found in US. Patent 2,576,792, issued November 27, 1951 to Scott R. Johnson, in which scroll strips from which to punch can ends, are successively cut from a metal sheet. When embodied in a machine of that general type, the present invention engages the sheet and effects the back-feed thereof after each advancing step imparted to said sheet. However, the sheetengaging means of the invention could well be employed in other environments requiring sheet shifting, whether the shifting be rearwardly or forwardly.

The invention like some of its predecessors, includes a friction shoe which is moved into contact with the sheet, pressed against said sheet and moved longitudinally of the sheet path to shift the sheet as required. Heretofore, it has been very diflicult to obtain such a differential between the shoe-to-sheet friction and the sheet-tosupport friction as to insure unerring sheet shifting upon each operation of the friction shoe. This difliculty has been found to be acute when feeding wax-coated sheets.

The present invention has aimed primarily to overcome the above mentioned difiiculty by opposing the pressure of the friction shoe against one side of the sheet by roller means contacting with the other side of said sheet, whereby the sheet will move freely on said roller means when said friction shoe is moved to back-feed or otherwise shift the sheet.

Another object of the invention has been to provide novel means for operating the friction shoe in a troublefree manner.

A further object has been to provide a novel construction well adapting the invention to a conventional scroll strip shearing machine and utilizing the up and down movements of the usual cross head, carrying the movable shear, to actuate the invention in timed relation with sheer operation.

With the above and other objects inview that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawings.

In the drawings:

FIGURE 1 is a fragmentary top view, partly broken away and in section, showing one form of the invention embodied in a scroll shear machine.

FIGURE 2 is a vertical longitudinal sectional view along line 2--2 of FIGURE 1, a number of the backgages and part of the hold-down bar on which they are mounted being omitted to show elements behind them.

FIGURE 3 is a vertical transverse section on line 33 of FIGURE 2.

FIGURE 4 is a top plan view, partly broken away and in section, showing the carriage of FIGURES 1 to 3 and the back-feed member thereon.

FIGURE 5 is a vertical longitudinal sectional view, partly in elevation, on line 55 of FIGURE 4.

FIGURE 6 is an enlarged fragmentary transverse sectional view on line 6-6 of FIGURE 4.

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FIGURE 7 is a top plan view, partly broken away and in section, showing the roller supporting and mountmg means of FIGURES 1 -to 3.

FIGURE 8 is an end elevation of FIGURE 7.

FIGURES 9 and 10 are vertical sectional views on lines 9-9 and lit-10 of FIGURE 7, respectively.

FIGURE 11 is a view, partly in elevation and partly in section, showing a different form of construction, the

friction shoe and the cross head carrying the upper shear being shown in raised position.

FIGURE 12 is a similar view showing the sheet backfed to the back gage and the upper shear and cross head lowered.

FIGURES 13 and 14 are views similar to FIGURES 11 and 12 but showing still another form of construction.

FIGURES 15, 16 and 17 are diagrams showing further variations.

The drawings conventionally illustrate a table 20 extending to a scroll shearing machine having a fixed lower die or shear 21, and a movable upper die or shear 22 mounted on a vertically reciprocable cross head 23. Rails 24 (FIGURE 1) are mounted on the table 20 to guide each sheet'25; fed bars 26 are provided for feedmg the sheet 25 step-by-step to the shear and for slightly over-feeding the sheet upon each advancing step; and back-gages 27 are provided against which to back-feed the sheet after each advancing step. The back gages 27 are shown in most views as'of the pivoted type disclosed in US. Patent 2,576,792 but they could well be of other suitable form, the essentials being that these gages shall not interfere with sheet advancing and shall function to limit the slight back-feedingmovement to be imparted to the sheet after said sheet is over-fed by the feed bars 26. Two sheet hold-down bars 28 are shown and serve as supports upon which the back-gages 27 are mounted. Two additional sheet hold-down bars 29 are also shown and these two bars are utilized in mounting a carriage 30 when the invention is to be of the form shown in FIGURES 1 to 10. All of the bars 28 and 29 are shown as secured to overlaying transverse bars 31 which are bracket-supported at 32 (FIGURE 1) upon the table 20.

The carriage 30 supports two friction shoes 33 in the present disclosure, and said carriage is actuated as hereinafter described to downwardly press said friction shoes against the sheet 25 and to then shift the over-fed sheet back to the back-gages 27. To oppose the downward pressure of the shoes 33, rollers 34 are mounted in the table 20 near the front end thereof. Thus, when the shoes 33 are depressed, the sheet 25 is gripped between said shoes 33 and the rollers 34 and frictional clinging 'of the sheet 25 to the table 20 connot therefore occur as said shoes 33 are moved to back-feed said sheet to the backgages 27. On the contrary, the rollers 34 will freely rotate and offer no resistance to the shifting of the sheet.

The carriage 30 and rollers 34 are shownon a small scale in the general assembly illustrated in FIGURES 1 t0 3. The construction of the carriage 30, however, is best seen in FIGURES 4 to 6, and the mounting means for the rollers 34 is best illustrated in FIGURES 7 to 10.

The carriage 30 includes two parallel longitudinal bars 35 and two transverse members 36 extending between and adjustably connected at 37 to said side bars 35. In the present disclosure, each transverse member 36 is a channel bar having blocks 38 secured in its ends and a third block 39 secured in its central portion. Brackets 40 are secured to the inner sides of the side bars 35 and extend under the end blocks 38. Tubular vertical screws 41 are threaded through the blocks 38 and the ends of the cross members 36vand rest on the brackets 40. These screws 41 are rotatably mounted on studs 42 carried by the brackets 40, and lock nuts 43 are provided for said screws 41. 'When the lock nuts 43 are loosened, the

screws 41 may be turned to adjust the cross members 36 with respect to the side bars 35, after which said lock nuts are again tightened.

A back feed member 44 extends longitudinally under the carriage cross members 36 and carries the friction shoes 33. In the present d'sclosure, the member 44 is a fiat shoe-carrying bar having blocks 45 secured upon its end portions. These blocks 45 contact with the lower sides of the central carriage blocks 39: and said blocks 45 are provided with suspending studs 46 which extend upwardly through short longitudinal slots 47 in said blocks 39 and the overlying portions of the cross members 36. Washers 46 and screws 46 hold the studs against withdrawal from the slots 47.

Spring means acts rearwardly on the back-feed member 44 and reacts on the foremost of the carriage cross members 36. The spring means 48 rearwardly biases the back-feed member 44 with respect to the carriage 30, to the limit allowed by the studs 46 and slots 47. When the carriage 30 is moved rearwardly (see FIGURE the spring means 48 moves the back feed member 44 to back-feed the sheet 25 to the back-gages 27: and upon any overtravel of said carriage 30 after the sheet abuts said back-gages 27, said spring means 48 yields and prevents injury to the sheet.

The side bars 35 of the carriage 30 rest slidably against the inner sides of the sheet hold-down bars 29: and said side bars 35 have cam slots 49 (FIGURES 1, 2, 4 and 5 which receive cam-follower-rollers 50 mounted on said bars 29. Each slot 49 has a horizontal front end 49" and a rearwardly declined end 49 (FIGURES 2 and 5). Whenever the carriage 30 occupies its forward position (FIGURES l and 2) the rollers 50 are seated in the rearwardly declined rear ends 49 of the slots 49 and the carriage is thus held at an elevation in which the friction shoes 33 are above the sheet 25. When the carriage 30 is moved rearwardly, however, (FIGURE 5) the inclined slot ends 49 coact with the rollers 50 in lowering the carriage and pressing the friction shoes 33 against the roller-supported sheet 25. Then, as the carriage 30 continues to move rearwardly to back-feed the sheet 25, the horizontal slot ends 49* coact with the rollers 50 in holding the carriage at a height for maintaining the shoe pressure against the sheet. When the carriage 30 again moves forwardly, it is restored to raised position by the coaction of the slot ends 48 and rollers 50.

The carriage 30, in the present disclosure, is moved rearwardly by the initial downward movement of the shear cross head 23. For this purpose, the carriage side bars, 35 have upstanding cam arms 51 cooperable with rollers 52 on brackets 53 secured to the cross head 23, as best seen in FIGURES 1 and 2. After the carriage 30 has back-fed the sheet 25 to the back-gages 27, said carriage simply idles as the cross head 23 completes its descent and cuts a scroll strip from the advanced sheet. As the cross head 23 returns upwardly, the carriage 30 is forwardly returned by springs 54 (FIGURES l and 2) acting on the side bars 35 and reacting on abutments 55 secured to the hold-down bars 29.

The rollers 34 may be mounted in any suitable manner but the preferred construction is shown on a small scale in FIGURES 1 to 3 and in detail in FIGURES 7 to 10. Two series of the rollers are shown and the rollers of each series are confined in a rectangular cage 56. These cages and the rollers thereof are confined in a horizontal channeled track member 57 having track plates 58 upon which the rollers 34 rest. The opposed inner sides of the channeled track member 57 have longitudinal track grooves 59 and the cages 56 have lateral lugs 60 slidably received in said grooves. The front end of the channeled track member 57 is closed by a plate 61 which serves to limit the forward movement of the foremost of the cages 56: and a stop 62 is secured upon the bottom of said track member to limit the forward movement of the rearmost of said cages. Bothcages are urged to their forward positions by springs 63 which react against adjustably mounted abutments 64. One of these abutments is secured to the bottom of the channeled track member 57 and the other is secured to the sub-structure 20 of the table 20. The track member 57 is inset in the table 2 with the peripheries of the rollers 34 projecting only a few thousandths of an inch above the upper surface of said table: and said track member has longitudinal side flanges 65 secured by screws 66 to the table sub-structure 20 Whenever the carriage 30 occupies its forward postion (FIGURES l and 2) the two roller cages 56 are held against the plate 61 and stop 62, respectively, by the springs 63. As soon as the carriage 30 has been lowered, during its rearward movement, to press the friction shoes 33 against the sheet 25 and to press this sheet 25 against the rollers 34, as in FIGURE 5, the continued rearward movement of said carriage causes said friction shoes 33 to back-feed the sheet 25. The rollers 34 then roll freely on the track plate 58 and on the lower side of the sheet 25 and present no appreciable resistance to the back-feeding of the sheet to the back-gages 27.

In the modification shown in FIGURES 11 to 17, the rollers 34 are supported by trunnions or shafts 67 and have no underlying tracks. Also, in FIGURES 11 to 14, the back gages 27a are shown as of a different known type and are positively actuated by known means. FIGURES 11 to 17 also illustrate other modifications described below.

In FIGURES 11 and 12, a vertically elongated carrier 68 for a single friction shoe 33 is shown. This carrier 68 is mounted on the shear cross head 23 by means of upper and lower, parallel rearwardly declined arms 69 and a bracket 70. The bracket 70 is secured for vertical adjustment to the cross head 23, the upper ends of the arms 69 are pivoted at 71 to said bracket, and the lower ends of said arms 69 are pivoted at 72 to the shoe carrier 68. A stop 73 limits the downward swinging movement of the arms 69 and a spring 74 yieldably holds said arms in lowered position when the cross head 23 is in raised position, as shown in FIGURE 11. The friction shoe 33 is then above the sheet 25. As the cross head 23 initially descends, the friction shoe 33 contacts with the rollersupported portion of the sheet 25. The continued descent of the cross head 23 then causes such swinging of the arms 69 as to move the carrier 68 and friction shoe 33 rearwardly, thus back-feeding the sheet 25 to the lowered back-gage or gages 27 as shown in FIGURE 12. Compare the distances A and B in FIGURES 11 and 12.

In FIGURES l3 and 14, a smaller carrier 68 is shown for a single friction shoe 33*. This carrier is mounted on the cross head 23 by means of a single rearwardly declined arm 69* and a bracket 70*. This bracket 70 is secured to the cross head 23, the upper end of the arm 69 is pivoted at 71 to said bracket 70, and the lower end of said arm 69 is pivoted at 72 to the carrier 68 The arm 69 is of suitable extensible and retractable construction to attain proper adjustment of the friction shoe 33 with respect to the rollers 34. This arm is shown as formed from two sections 74 and 75 adjustably connected at 76.

The construction of FIGURES l3 and 14 operates in the same manner as that of FIGURES 11 and 12. Compare FIGURES l3 and 14 and the distances C and D thereon.

In FIGURE 15, the friction shoe carrier 77 receives only horizontal movements to back-feed the sheet 25, and the roller carrier 78 receives vertical movements to cause gripping and releasing of said sheet 25.

In FIGURE 16, the friction shoe carrier 77 is under the sheet path and the roller carrier 78 is over said path. The friction shoe carrier 77 receives only horizontal movements to back-feed the sheet 25, and the roller carrier 78 receives only vertical movements to cause gripping and releasing of said sheet.

In FIGURE 17, the friction shoe carrier 77 is under the sheet path and the roller carrier 78 is over said path. The friction shoe carrier 78 receives both vertical and horizontal movements to effect sheet gripping and backfeeding.

The required relative movements of the friction shoe carrier and the roller carrier of FIGURES 15, 16 and 17 may be attained by adequate actuating means well within the field of mechanical skill and not therefore illustrated.

From the foregoing it will be seen that novel and advantageous part structure and arrangement has been disclosed for attaining the desired ends, but attention is inv-ited to the possibility of making variations within the scope of the invention. For example, the shaft-or-trunnion-supported rollers of FIGURE 15 could well be employed instead of the caged track-supported rollers of FIGURES 1 and 2, and vice versa.

I claim:

1. In a machine in which a sheet is to be shifted longitudinally of a sheet support, sheet-gripping means associated with said support and including a substantially fiat friction shoe disposed for contact with one side of the sheet and freely rotatable roller means disposed for contact with the other side of said sheet, said friction shoe and roller means being in opposed normally spaced relation with each other for freely receiving a sheet therebetween and each roller axis of said roller means being at a right angle to the path along which the sheet is to be shifted, and operating means for said sheet-gripping means including means for first relatively moving said shoe and roller means vertically to cause pressure gripping of the sheet between said shoe and said roller means and for then shifting said shoe longitudinally of said path with respect to said roller means, whereby said roller means will roll as the sheet is shifted and will present no appreciable resistance to sheet shifting.

2. In a machine in which a sheet is over-fed step-bystep along a support extending to a mechanism for operating upon said sheet, and in which the sheet is back-fed to a back-gage after each advancing step; sheet-gripping means associated with said support and including a substantially fiat back-feed shoe disposed for contact with one side of the sheet and freely rotatable roller means disposed for contact with the other side of said sheet, said back-feed shoe and roller means being in opposed normally spaced relation with each other for freely receiving a sheet therebetween and each roller axis of said roller means being at a right angle to the path along which the sheet is fed, and operating means for said sheet-gripping means including means for relatively moving said shoe and roller means vertically to cause pressure gripping of the sheet between said shoe and said roller means and for then shifting said shoe rearwardly with respect to said roller means to back-feed the sheet to the backa e. g The machine of claim 1, in which said roller means is disposed under the sheet path, and in which said shoe is disposed over said sheet path and is shifted both vertically and horizontally by said operating means to respectively grip and shift the sheet.

4. The machine of claim 1, in which said roller means is disposed under the sheet path and receives vertical movement to cause sheet gripping, and in which said shoe is disposed over said path and receives horizontal movement to shift the sheet.

5. The machine of claim 1, in which said roller means is disposed over the sheet path and receives vertical movement to cause sheet gripping, and in which said shoe is disposed under said path and receives horizontal movement to shift the sheet.

6. The machine of claim 1, in which said roller means is disposed over the sheet path, and in which said shoe is disposed under said path and receives both vertical movement to cause sheet gripping and horizontal movement to shift the sheet.

7. The machine of claim 1, in which said roller means comprises a series of closely spaced rollers having their axes disposed in parallel relation, a fixed horizontal track member supporting said series of rollers under the sheet path, and a cage containing said rollers and permitting free rolling thereof on said track member.

8. In a machine in which a sheet is over-fed step-bystep along a support to a mechanism having a vertically reciprocable member for operating on said sheet, and in which the sheet is back-fed to a back-gage after each advancing step; the improvement comprising a carriage above the path along which the sheet is fed, means mounting said carriage for horizontal movement toward and from said vertically reciprocable member, operating means for said carriage including means for moving it downwardly and then rearwardly when said vertically reciprocable member descends and for moving it again forwardly and upwardly when said member ascends, a back-feed member mounted on said carriage for limited movement forwardly and rearwardly with respect thereto, said back-feed member having a friction shoe to contact with the sheet, coacting stop means on said carriage and said back-feed member for limiting the rearward movement of said back-feed member with respect to said carriage, and spring means acting on said back-feed member for yieldably holding said back-feed member in its rearward position with respect to said carriage whenever said carriage occupies its forward position'; whereby said back-feed member will be moved downwardly and rearwardly by said carriage to back-feed the sheet to the back gage and said spring means will then yield to allow rearward over-travel of said carriage.

9. In a machine in which a sheet is over-fed step-bystep along a support to a mechanism having a vertically reciprocable memberfor operating on said sheet, and in which the sheet is back-fed to a back-gage after each advancing step; the improvement comprising a carriage above the path along which the sheet is fed, said carriage having parallel horizontal side members, means slidably engaging said side members and mounting said carriage for movement toward and from said vertically reciprocable member, said means including coacting cams and followers for depressing said side members as they are moved rearwardly and for again raising said side members as they are again moved forwardly, means acting on said side members for moving said carriage rearwardly when said vertically reciprocable member descends, spring means acting on said carriage for moving it forwardly when said vertically reciprocable member ascends, a back-feed member mounted on said carriage for limited movement forwardly and rearwardly with respect thereto, said back-feed member having a friction shoe to contact with the sheet, coacting stop means on said carriage and said back-feed member for limiting the rearward movement of said back-feed member with respect to said carriage, and spring means acting on said back-feed member for yieldaibly holding said back-feed member in its rearward position with respect to said carriage whenever said carriage occupies its forward position; whereby said back-feed member will be moved downwardly and rearwardly by said carriage to backfeed the sheet to the back gage and said spring means will then yield to allow rearward over-travel of said carriage.

10. A structure as specified in claim 8, in which provision is made for vertically adjusting said back-feed member with respect to said carriage.

11. A structure as specified in claim 9, in which said carriage includes across member and adjusting means connecting the ends of said cross member with said side members to allow vertical adjustment of said cross members, said back-feed member being connected to said cross member.

12. In a machine in which a sheet is over-fed step-bystep along a support to a mechanism having a vertically reciprocable member for operating on said sheet, and in which the sheet is back-fed to a back-gage after each advancing step; the improvement comprising a carriage above the path along which the sheet is fed, said carriage including front and rear transverse members each having a slot elongated in the direction of the sheet path, means mounting said carriage for horizontal movement toward and from said vertically reciprocable member, operating means for said carriage including means for moving it downwardly and then rearwardly when said vertically reciprocable member descends and for moving it again forwardly and upwardly when said vertically reciprocable member ascends, a longitudinual member under the aforesaid cross members of said carriage, said longitudinal member having front and rear upwardly projecting suspending studs slidably received in the aforesaid slots respectively, a back-feed friction shoe carried by said longitudinal member in position to engage the sheet when said carriage is moved downwardly and rearwardly,

and spring means acting on said longitudinal member and reacting on one of said cross members for biasing said longitudinal member rearwardly to the extent permited by said slots and studs.

13. In a machine in which a sheet is over-fed step-bystep along a support extending to a mechanism for oper ating upon said sheet, and in which the sheet is back-fed to a back-gauge after each advancing step; a carriage above the path along which the sheet is fed, means mounting said carriage for horizontal movement in the general direction of said sheet, means for moving said carriage downwardly and then rearwardly and means for moving said carriage forwardly and then upwardly, a back-feed member mounted on said carriage for movement therewith, said back-feed member having a friction shoe for contacting with the sheet, coaeting stop means on said carriage and said back-feed member for limiting the rearward movement of said back-feed member with respect to said carriage, and spring means acting on said backfeed member for yieldably holding said back-feed member in its rearward position with respect to said carriage whenever said carriage occupies its forward position, whereby said back-feed member will be moved downwardly and rearwardly by said ctrriage to back feed the sheet to the back gauge and said spring means will then yield to allow rearward over-travel of said carriage.

14. In a machine in which a sheet is over-fed step-bystep along a support extending to a mechanism for operating on said sheet, and in which the sheet is back-fed to a back-gauge after each advancing step; a carriage above the path along which the sheet is fed, said carriage having parallel horizontal side members, cam slots formed in said carriage side members, support means for said carriage including cam followers seated in said cam slots, said cam slots having upwardly and forwardly sloping rear portions and horizontally extending forward portions whereby rearward movement of said carriage will result in the initial rearward and downward movement of said carriage and a final horizontal movement of said carriage, means for imparting a horizontal only thrust on said carriage to effect a rearward movement of said carriage, spring means for returning said carriage to its initial position, a back-feed shoe carried by said carriage for movement therewith, roller sheet support means overlying said shoe and cooperating with said shoe to permit a gripping of a sheet by said shoe as said shoe is rolled with said carriage and a rearward movement of the sheet with no appreciable resistance to the movement thereof by said shoe as said carriage is moved directly rearwardly.

15. The machine of claim 1 wherein said roller means includes a plurality of individual rollers disposed in closely spaced side-by-side relation, and the length of said friction shoe being at least equal to two times the diameter of each roller plus two times the spacing between adjacent rollers whereby a sheet will be gripped between the friction shoe and at least two rollers at all times during the sheet feeding operation.

16. The machine of claim 1 wherein said friction shoe has a smooth sheet engaging surface whereby damage to sheet finish by engagement of the friction shoe therewith is prevented.

17. The machine of claim 1 wherein the operating means for moving said shoe includes a downwardly biased arm supporting said shoe, a vertically reciprocable member for operating on the sheet, said arm being disposed behind said vertically reciprocable member and pivoted thereto on a horizontal axis transverse to the path along which the sheet is fed, and means for limiting the downward swinging of said arm.

18. The machine of claim 17 in which said arm is manually extensible and retractable.

19. The machine of claim 1 wherein the operating means for moving said shoe includes upper and lower downwardly biased arms, a vertically reciprocable member for operating on the sheet, said arms being disposed behind said vertically reciprocable member and pivoted thereto on parallel horizontal axes which are transverse tothe path along which the sheet is fed, a carrier for said shoe pivoted to the lower ends of said arms on axes which are parallel with and spaced downwardly and rearwardly from the first mentioned pivotal axes of said arms, and means for limiting the downward swinging of said arms.

20. A sheet feeding mechanism comprising a sheet sup port, a stop gauge positioned along said sheet support for facilitating the positioning of a sheet along said sheet support, a carriage, means mounting said carriage above the path along which a sheet is fed and for back and forth horizontal movement, operating means connected to said carriage for first moving said carriage downwardly and then linearly rearwardly and for secondly moving said carriage forwardly and linearly upwardly, a sheet-feed member mounted on said carriage for limited movement forwardly and rearwardly with respect to said carriage, said sheet-feed member having a friction shoe to contact with the sheet, coaeting stop means on said carriage and said sheet-feed member for limiting the rearward movement of said sheet-feed member with respect to said carriage, and spring means acting on said sheet-feed member for yieldably holding said sheet-feed member in its rearward position relative to said carriage whenever said carriage occupies its forward position, whereby said sheetfeed member will be moved downwardly and rearwardly by said carriage to feed the sheet to said stop gauge and said spring means will then yield to allow rearward overtravel of said carriage.

References Cited in the file of this patent UNITED STATES PATENTS 1,194,728 Ennes et al. Aug. 15, 1916 1,346,589 Cameron July 13, 1920 1,847,857 Ames Mar. 1, 1932 2,339,756 Aneiros Jan. 25, 1944 2,355,873 Faille Aug. 15, 1944 2,439,070 Bailey et al Apr. 6, 1948 2,576,792 Johnson Nov. 27, 1951 2,635,875 Werner Apr. 21, 1953 

1. IN A MACHINE IN WHICH A SHEET IS TO BE SHIFTED LONGITUDINALLY OF A SHEET SUPPORT, SHEET-GRIPPING MEANS ASSOCIATED WITH SAID SUPPORT AND INCLUDING A SUBSTANTIALLY FLAT FRICTION SHOE DISPOSED FOR CONTACT WITH ONE SIDE OF THE SHEET AND FREELY ROTATABLE ROLLER MEANS DISPOSED FOR CONTACT WITH THE OTHER SIDE OF SAID SHEET, SAID FRICTION SHOE AND ROLLER MEANS BEING IN OPPOSED NORMALLY SPACED RELATION WITH EACH OTHER FOR FREELY RECEIVING A SHEET THEREBETWEEN AND EACH ROLLER AXIS OF SAID ROLLER MEANS BEING AT A RIGHT ANGLE TO THE PATH ALONG WHICH THE SHEET IS TO BE SHIFTED, AND OPERATING MEANS FOR SAID SHEET-GRIPPING MEANS INCLUDING MEANS FOR FIRST RELATIVELY MOVING SAID SHOE AND ROLLER MEANS VERTICALLY TO CAUSE PRESSURE GRIPPING OF THE SHEET BETWEEN SAID SHOE AND SAID ROLLER MEANS AND FOR THEN SHIFTING SAID SHOE LONGITUDINALLY OF SAID PATH WITH RESPECT TO SAID ROLLER MEANS, WHEREBY SAID ROLLER MEANS WILL ROLL AS THE SHEET IS SHIFTED AND WILL PRESENT NO APPRECIABLE RESISTANCE TO SHEET SHIFTING. 